Boat steering and reversing system

ABSTRACT

A system for controlling the forward and reverse operation of a boat having a propulsion unit which is rotated to provide normal steering of the boat. Included is a mechanism for providing a rapid rotated of the propulsion unit through a turn of approximately one-half circle to redirect the force of propulsion forwardly and thus provide reversal of the boat. The mechanism includes operating elements operatively connected to and controlled at the steering wheel itself for providing the changeover between forward and reverse operation.

United States Patent 1191 1111 3,756,188 Smith 1451 Sept. 4, 1973 BOAT STEERING AND REVERSING 3,148,657 9/1964 Homing 115/35 SYSTEM Inventor: Joseph E. Smith, Birmingham, Mich.

Wolverine-Pentronix, 1nc., Lincoln Park, Mich.

Filed: Mar. 1, 1972 Appl. No.: 230,687

Assignee:

US. Cl. 115/35 Int. Cl B63h 25/42 Field of Search 115/35, 34; 114/154,

References Cited UNITED STATES PATENTS Bossen 115/35 Willis, Jr 115/35 Primary ExaminerMilton Buchler Assistant ExaminerCarl A. Rutledge Attorney- Robert C. Hauke, Claude A. Patalidis et al.

[57] ABSTRACT A system for controlling the forward and reverse operation of a boat having a propulsion unit which is rotated to provide normal steering of the boat. Included is a mechanism for providing a rapid rotated of the propulsion unit through a turn of approximately one-half circle to redirect the force of propulsion forwardly and thus provide reversal of the boat. The mechanism includes operating elements operatively connected to and controlled at the steering wheel itself for providing the changeover between forward and reverse operation.

17 Claims, 9 Drawing Figures PATENTEDsEP 4 ma SHEET 1 [IF 2 PATENTEDSEP 4 ms SHEET 2 OF 2 Fig? Fig-6 .1mm UMP BOAT STEERING AND REVERSING SYSTEM BACKGROUND OF THE INVENTION This invention relates to steering and reversing systerns for boats in which there is included a propulsion unit adapted to provide a thrust force rearwardly of the boat. The invention is particularly related to those propulsion systems in which the propulsion unit is rotated about an upstanding and substantially vertical axis to provide for a controllable steering of the boat without requiring the use of a separate rudder or like steering mechanism. The propulsion unit itself may incorporate a modified rudder to provide desired rudder effect.

It will be seen that the present invention in its several different embodiments may be applied to a boat drive system in which the engine is either inboard or outboard mounted and in which a propeller is included to provide the force for propelling the boat forwardly. The present invention is equally applicable to a jet propulsion system for a boat of the type in which the propulsion unit includes an orifice through which water can be discharged under pressure to provide a thrust force to propel the boat. In either case. the changeover as between the forward and reverse operation of the boat is achieved through a rapid reversing mechanism which is effective to reorient the propulsion unit and the thrust force it provides between forward and reverse directions relative to the boat.

SUMMARY OF THE PRESENT INVENTION The present invention relates to a rapid reversal mechanism for reorienting a boat propulsion unit, which reversal is provided without requiring a complicated reverse drive and gear mechanism for the drive system. The present invention is so designed as to make this reversal suffiently rapid to minimize disturbing influence from the side torques which would ordinarily be encountered while the 180 reversing turn is being made. A suitable interlock may be provided between the throttle control for the engine to provide engine idling during the 180 turn. Altemately, an interlock may be provided with a clutch mechanism to disconnect the drive from the propeller during the 180 turn.

The mechanism according to the present invention is situated in a position in which it may be readily operated by the boat operator without interfering with normal steering operation of the boat. The control is directly and operatively connected to the steering wheel itself so that the control of the boat direction as it is made during forward drive or during docking procedures is greatly facilitated.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood by reference to the accompanying specification and to the accompanying drawings in which like reference characters are used to refer to like parts throughout the several views, and in which:

FIG. 1 is a partly perspective view with parts broken away showing a propulsion unit as it is mounted on the rear transom of the boat and further showing the cable and gear used to interconnect the forward steering wheel and the propulsion unit for swiveling it;

FIG. 2 is a top plan view of one embodiment of the present invention using a planetary gear set connected integral with the steering wheel;

FIG. 3 is a transverse sectional view of a fluid actuator operated embodiment of the present invention;

FIG. 4 is an elevational view of the device of FIG. 3;

FIG. 5 is a top plan view of a further embodiment of the present invention in which an electrical motor operator is used;

FIG. 6 is an elevational view of the device of FIG. 5;

FIG. 7 is a schematic drawing of a circuit used to operate the device of FIG. 5;

FIG. 8 is a top plan view of a still further embodiment of the present invention using a manually operated reversing lever; and

FIG. 9 is an elevational view of the device of FIG. 8.

DETAILED DESCRIPTION OIF THE SEVERAL ALTERNATE EMBODIMENTS As shown in FIG. 1, the rear transom of the boat 20 has mounted on it a drive or propulsion unit indicated generally by the numeral 22. The engine which is used to drive the boat has been omitted from the drawing in the interest of brevity. The engine is normally coupled to a vertical drive shaft 24 to provide to it a variable speed rotative drive. At the lower end of the drive shaft 24 there is included a drive pinion 26 which meshes with the teeth of a driven gear 28 to provide a driving rotation to it. Gear28 is pinned to the left end of a propeller shaft 30. A propeller 32, mounted at the right end of the shaft 30, is bladed to provide a force rearwardly of the boat to provide its forward propulsion. Suitable bearings 34 and 36 are used to provide a rotative support to the shafts 24 and 30. It will be seen that the propulsion unit 22 further includes a mounting bracket 37 which has its upper end 370 clamped over the transom 38. A bearing retainer 39 is fixed to the lower end of the bracket 37 by a bolt 40. Supported for rotation about a substantially vertical axis is a steering tube 42, which is shown with its central portion broken away. The steering tube 42 is interconnected with and operable to rotate the lower housing 38a which contains the lower portion of the propulsion unit 22 including the propeller 32. Fixed at the upper end of the steering tube 42 is a toothed gear 44 which has its teeth engageable with those of an aligned rack gear 46. The rack gear 46 is longitudinally movable and connected to a steering cable 50, which in turn is coupled to a forward located steering wheel 56. Responsive to the force applied by the cable 50, the rack gear 46 will be displaced and the steering tube 42 will then be rotated through its gear portion 44 about .an axis which is substantially perpendicular to the longitudinal axis of the boat 20. In the interest of simplification, a detailed description and showing of the engine and its associated throttle and clutch mechanism has been eliminated.

FIG. 2 shows one of the embodiments of the present invention incorporated with the steering wheel 56. The steering wheel 56 has mounted on it a ring gear 58. The ring gear 58 comprises a part of a planetary gear system, which further includes three planetary gears 60, 62 and 64 which are rotatively mounted on pins 60a, 62a and 640, respectively, extending downwardly from the underside of a manually rotatable plate 66. The planetary gear set is completed by a central or sun gear 68 mounted at the upper end of a steering shaft 70. The rotative movement of the steering shaft 70 is changed into a linear movement of a rack gear 72, whose teeth are held in mesh with a second pinion gear 71 mounted on the shaft 70 below the first mentioned pinion 68.

The plate 66 and an attached lever 74 comprise a reverse control means for changeover of operation of the boat between a forward and reverse operation. For this purpose a reversing cable 76 may be connected to the lever 74 extending from the plate 66. Alternately, the lever 74 max be directly actuated by the operator. During the normal forward operation of the boat, the lever 74 is held stationary by the reverse cable 76. The tuming of the steering wheel 56 rotates with it the ring gear 58. This results in the rotation of the pinion gears 60, 62 and 64 upon their respective pins 60a, 60b and 60c. The rotation of the pinion gears then turns the pinion 68 and the steering shaft 70 to which it is fixed. The lower pinion 71 has its teeth in engagement with the teeth of the rack gear 72 to provide a movement of the steering cable 50 and a selective steering to the propulsion unit 22.

In order to place the propulsion unit 22 in its reverse operating position, the lever 74 is displaced leftwardly. The downwardly extending pins 60a, 62a and 64a which carry, respectively, pinion gears 60, 62 and 64 are thus displaced to rotate the pinion gears about the axis of the pinion 68 and the steering shaft 70. The sun gear 68 is thus rotated a predetermined amount with the shaft 70. The lower pinion 71 is thus rotated a predetermined amount with the shaft 70. The lower pinion 71 fixed to shaft 70, which has its teeth engaged with the teeth of the rack 72, is rotated to cause a linear movement of the rack 72 and of the steering cable 50 in a direction and for a distance sufficient to rotate the propulsion unit 22 through substantially 180 and into a reverse position. This swiveling is provided through the action of the rearwardly located rack 46 and the gear 44 at the upper end of the steering tube 42. This particular embodiment of the present invention has advantages since it is located immediately at the steering wheel and may readily be manipulated by the operator to permit the changeover into and away from reverse operation of the propulsion unit 22.

FIG. 3 illustrated a difierent embodiment of the present invention in which a rotary fluid actuator is used to provide the changeover between forward and reverse operation of the boat. For this purpose, the steering wheel 56 has mounted in it a central opening 81 formed inwardly of the steering shaft 70. Extending inwardly from the central opening 81 are a pair of limiting extensions 82 and 84 which define the end limits of movement of the shaft 70 with respect to the steering wheel 56. The arcuate chamber 81 further includes a pair of conduits 83 and 85 which are used to admit pressurized fluid to provide the selective movement of an arcuately movable vane 86 extending outwardly from the steering shaft 70 and rotatably movable between the stops 82 and 84. A suitable hydraulic or pneumatic valve means, not shown but of a type well known to the art, may be used to provide admission of a pressure P through conduit 83 or alternately a pressure P, through the conduit 85 to provide the appropriate actuation of the vane 86. It will be seen that in a normal forward drive condition with pressure applied through the conduit 85 at P, and conduit 83 connected to exhaust or to ambient, the piston will be biased counterclockwise against the stop 82. A rotation of the steering shaft 70 will cause a displacement of a lower rack 72, which has its teeth in mesh with a pinion 70a fixed at a position below piston 86 on the steering shaft 70. In this manner, there is provided a predetermined linear movement of the rack 72 and of the steering cable 50, which motion is transmitted to a rotation of the propulsion unit 22 through its associated pinion and rack gear connection. When changeover is desired to a reverse operating condition, operating pressure is admitted by a suitable control valve through the conduit 83 at P to rotate the vane 86 to the opposite end in abutment with the lower stop 84. At the same time, conduit is connected to exhaust or to ambient. In this case, the pinion 70a, fixed to the steering shaft 70 and in mesh with the rack gear 72, is likewise rotated a predetermined amount thus rotating the propulsion unit 22 through its rack and gear connection to place it in its reverse operation condition.

FIG. 4 is a view illustrating the manner in which the central chamber 81 is formed in the steering wheel 56 and further showing the lower extension of steering shaft 70 and the manner in which the pinion 70a is mounted on it with its teeth in mesh with the drive rack 72 to provide its linear displacement. Also shown is the rotary vane 86 fixed at the upper end of the steering shaft 70.

FIGS. 5 and 6 show a different embodiment of the present invention in which there is employed an electrical torque motor which operates its armature 90 to provide a rapid reversing drive of the propulsion unit 22. In the embodiment of FIGS. 5 and 6, the steering wheel 56 is mounted at the upper end of the shaft 70. A lower pinion 68 is also fixed to the shaft 70. The teeth of the pinion 68 are in mesh with the rack 72, which in turn is connected to the steering cable 50. The steering cable 50, as in the other embodiments of the invention, is connected at a rearward point to the rack gear 46 and through a gear connection to the steering tube 42 associated with the boat propulsion unit 22. The armature 90 is rotatably mounted within the steering wheel 56. Alternately, the armature may be mounted on the shaft 70 at a point below the wheel 56. The torque motor armature 90 further has fixed to it a detent 92, which detent is movable between a pair of spaced stops 94 and 96 formed and extending inwardly from the rim of the steering wheel 56. The armature 90 is additionally fixed to the pinion 68 through the shaft 70. When the field applied to the armature 90 is reversed in a manner well known to the electrical art, the armature 90 is provided with a force in a clockwise direction so that the detent 92 attached to it becomes limited against the stop 96 on the steering wheel. This rotation serves to position the steering cable 50 independently of the turning of the steering wheel 56 to provide the necessary rotation of the propulsion unit 22.

FIG. 7 shows the circuit by which reversal of the operation of the armature 90 of the torque motor is achieved. A DC bias source 89 is connected to the motor field 91. The reversal of polarity applied to the tenninals of the motor field 91 is provided through the manual actuation of a switch 93. In the upper position of a pair of movable contacts 930 and 93b, the polarity applied to the field 91 is minus upper and positive lower, while in the lower position of the switch contacts the polarity is reversed.

FIGS. 8 and 9 show a different embodiment of the present invention in which there is provided a manually operable reversing lever mounted on the upper end of the steering shaft 70. As shown before in the other embodiments, a pinion 68 is fixed to the shaft 70 and has its teeth engageable with the teeth of the longitudinally movable rack 72 to which the steering cable 50 is connected. FIG. 8 shows both the unmoved and moved positions of the reversing detent lever 100 as it is placed in the forward and reverse operating conditions. The reversing lever 100 is pivotably mounted near the upper end of the shaft 70 by pin 106. The lever 100 includes a recessed end portion 102 engageable with a pair of leftward and rightward located stop pins 103 and 104, which pins are fixed to the steering wheel 56. During the normal forward operation of the boat, the reversing lever 100 is in its left hand solid line designated position. As the steering wheel 56 is turned, the pin 103 mounted on steering wheel 56 turns the reversing lever 100 with it, thus turning the shaft 70 and rotating the gear 68 to provide a proper linear displacement of the rack gear 72 and thus steering the propulsion unit 22. When it is necessary to change the operation of the boat into reverse, the reversing lever 100 is first tilted upwardly slightly to raise it above the stop pin 102. The lever 100 is then rotated clockwise and placed downwardly to lock it about the stop pin 104. This motion of the lever 100 causes a corresponding predetermined rotation of the shaft 70 and the gear 68. The steering wheel 56 can then-be turned to provide the necessary steering of the propulsion unit 22 during the continued reverse operation of the boat.

It will thus be seen that by the present invention there has been provided a substantially improved and novel mechanism for providing for a control and a rapid changeover between forward and reverse operation of the boat. The particular type of mechanism employed is one which is readily adaptable for incorporation with the steering wheel to simplify its handling and the actuation of the reversing mechanism by the operator.

What is claimed is: control 1. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical drive axis for steering the boat, a steering control means, a connecting means coupled between said steering control means and said unit for turning it for normal steering, and a reverse control means operatively connected to said propulsion unit for rotating it rapidly through a substantially 180 turn to provide for changeover between forward and reverse operation of the boat, said reverse control means operatively mounted on said steering control means and actuable independently of said steering control means for providing the changeover between forward and reverse operation.

2. The combination as set forth in claim 1 wherein said reverse control means comprises a first gear mounted on said steering means, a second gear means engageable with said first gear and operably coupled to said connecting means, and a reversing control lever operatively connected with said gears for changing their positions one relative to the other and thereby rotating said propulsion unit through said turn.

3. The combination as set forth in claim 2 wherein said first gear comprises a ring gear fixed to said steering means and wherein said second gear means comprises a set of planetary gears having their teeth engageable with said ring gear and arcuately displaceable relative to it during said turn.

4. The combination as set forth in claim 2 wherein said second gear means further includes a sun gear having its teeth continuously engageable with said planetary gears, said steering means mounted on a steering shaft and said sun gear fixed proximate the upper end of said steering shaft.

5. The combination as set forth in claim 2 wherein said steering means comprises a steering shaft and a steering wheel fixed to said shaft, wherein said first gear comprises a ring gear mounted on said wheel, wherein said second gear means comprises a set of planetary gears having teeth engageable with the teeth of said ring gear, wherein a sun gear pinion is mounted on the upper end of said shaft having its teeth engageable with said planetary gear teeth, and wherein a second pinion gear is mounted on said steering shaft at a point spaced from said sun gear for driving engagement with a rack gear to provide a predetermined movement of said connecting means and said propulsion unit.

6. The combination as set forth in claim 1 wherein said connecting means includes a steering cable, said cable having a rack gear connected at its forward end, said steering means further having a pinion gear fixed to it for rotation therewith, said pinion gear having its teeth in mesh with the teeth of said rack for turning said propulsion unit.

7. The combination as set forth in claim 3 wherein a reversing lever is operably coupled to said planetary gear set to provide its displacement relative to said ring gear to provide said propulsion unit turn.

8. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical axis for steering the boat, a rotatable steering wheel, a steering cable connected between said steering wheel and said propulsion unit for rotating it for normal steering, and a control mechanism operatively connected to said propulsion unit for rotating it rapidly through a substantially turn to provide changeover between for ward and reverse operation, said mechanism including a reverse control means operably mounted on said steering wheel and manually rotatable a predetermined arcuate distance about the axis of said steering wheel, said last mentioned means coupled to said steering cable for providing said turn.

9. The combination as set forth in claim 8 wherein said steering wheel is mounted on a shaft, said shaft rotatable independently of said steering wheel to rotate said unit, and wherein said control means comprises a fluid actuator device connected to said shaft for providing its rotation.

10. The combination as set forth in claim 9 wherein said actuator device comprises a rotary operated fluid motor, said motor having a vane operable between two spaced stops mounted on said steering wheel for providing changeover between the forward and reverse operation of the propulsion unit.

11. The combination as set forth in claim 9 wherein the rotative movement of said shaft is communicated to said steering cable and to said propulsion unit through a pinion fixed to said shaft and a rack gear in mesh with said pinion and coupled to the forward end of said cable.

12. The combination as set forth in claim 8 wherein said propulsion unit includes a motor driven propeller mounted on said propulsion unit and swivelable therewith.

13. In a boat having a propulsion unit mounted on it and rotatable about an upstanding axis for steering the boat, a rotatable steering wheel, a connecting means coupled between said steering wheel and said propulsion unit for rotating it for normal steering, and a control means operatively connected to said propulsion unit for rotating it rapidly through substantially a half circle turn to provide for a reversal of the boat drive, said control means comprising a detent lever mounted on said steering wheel and operably coupled to said connecting means for providing a predetermined rotation of said propulsion unit independently of the rotation of said steering wheel.

14. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical axis for steering the boat, a rotatable steering wheel, a steering cable connected between said steering wheel and said propulsion unit for rotating it for normal steering, and a control means operatively connected to said propulsion unit for rotating it rapidly through a turn of substantially 180 to provide a reversal of the boat drive, said control means comprising an electrically operated means mounted on said steering wheel and operable to rotate independently of said steering wheel and displace said cable a predetermined amount to provide said turn to provide the changeover between forward and reverse operation of the boat.

15. The combination as set forth in claim 14 wherein said electrically operated means comprises the armature of a torque motor, said torque motor further having its field operatively connected to and controlling the direction of movement of said armature and the movement of said steering cable, and a switching means for reversing the polarity across said motor field.

16. The combination as set forth in claim 14 wherein said steering wheel is coupled to a steering shaft and said electrically operated means is fixed to said shaft and movable between a pair of spaced stops mounted on said steering wheel to provide said turn.

17. The combination as set forth in claim 14 wherein said wheel is mounted on a steering shaft, said shaft having a pinion gear mounted on it and a toothed rack engageable with the teeth of said pinion gear and attached to one end of said cable for providing the required movement of said steering cable.

* i l i UNITED STATES PATENT OFFICE CERTH KCATE OF CORRECTION Pate t 3,75 8 Dated September a, 1973 JOSEPH E. SMITH Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

IN THE ABSTRACT Line A, change "rotated" to rotation IN THE SPECIFICATION Column 5, line 6, correct the spelling of "may" line LFO, change "FIG. 3" to S I FIGS. 3 and line 65 change "70a" to '71 cancel "at a position" line 66, cancel "below piston 86" Column A, line 10, change "70a" to 71 lines 15-22, cancel line 29, change "68" to 71 line 50, change "68" to .71

line E3 change "68" to '71 Column A, line 59, cancel "minus upper and positive" line 60, cancel "lower" and insert thereinstead in a given direction,

FORM PO-105O (10-69) USCOMM-DC 603764 69 fl' LLS. GOVERNMENT PRINTING OFFICE I9! 0-366-33l.

Page 2 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,756,188 Dated September 973 Inventor s) JOSEPH E SMITH It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

line 65, cancel "shown before" line 66, change "68" to '71 Column 5, line 2, cancel "the unmoved and moved" and insert thereinstead extreme line 15, change "68" to 71 line 23, change "68" to 71 line 35, cancel "control" IN THE DRAWING FIG. A, change reference numeral "70a" to 71 FIG. 5, add reference numeral 90 FIG. 8, add a pin in dotted line along a diameter of shaft 70, and identify the same by reference numeral 106 F ORM PO-1050 (10-69) USCOMM-DC 60376-P69 u.s eovlmmiwr PRINTING orrlc! Ill! o-usqu,

. Page 5 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,756,188 Dated September A, 1975 Inventor-(s) V E It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

FIG. 9, change reference numeral "68" to 71 Signed and sealed this 20th day of Au ust 197 (SEAL) Attest:

McCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents ORM PC1-1050 (IO-69) USCOMM-DC 60376-P69 U.S, GOVERNMENT PRINTING OFFICE l9 O3$fi-3Jl. 

1. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical drive axis for steering the boat, a steering control means, a connecting means coupled between said steering control means and said unit for turning it for normal steering, and a reverse control means operatively connected to said propulsion unit for rotating it rapidly through a substantially 180* turn to provide for changeover between forward and reverse operation of the boat, said reverse control means operatively mounted on said steering control means and actuable independently of said steering control means for providing the changeover between forward and reverse operation.
 2. The combination as set forth in claim 1 wherein said reverse control means comprises a first gear mounted on said steering means, a second gear means engageable with said first gear and operably coupled to said connecting means, and a reversing control lever operatively connected with said gears for changing their positions one relative to the other and thereby rotating said propulsion unit through said turn.
 3. The combination as set forth in claim 2 wherein said first gear comprises a ring gear fixed to said steering means and wherein said second gear means comprises a set of planetary gears having their teeth engageable with said ring gear and arcuately displaceable relative to it during said turn.
 4. The combination as set forth in claim 2 wherein said second gear means further includes a sun gear having its teeth continuously engageable with said planetary gears, said steering means mounted on a steering shaft and said sun gear fixed proximate the upper end of said steering shaft.
 5. The combination as set forth in claim 2 wherein said steering means comprises a steering shaft and a steering wheel fixed to said shaft, wherein said first gear comprises a ring gear mounted on said wheel, wherein said second gear means comprises a set of planetary gears having teeth engageable with the teeth of said ring gear, wherein a sun gear pinion is mounted on the upper end of said shaft having its teeth engageable with said planetary gear teeth, and wherein a second pinion gear is mounted on said steering shaft at a point spaced from said sun gear for driving engagement with a rack gear to provide a predetermined movement of said connecting means and said propulsion unit.
 6. The combination as set forth in claim 1 wherein said connecting means includes a steering cable, said cable having a rack gear connected at its forward end, said steering means further having a pinion gear fixed to it for rotation therewith, said pinion gear having its teeth in mesh with the teeth of said rack for turning said propulsion unit.
 7. The combination as set forth in claim 3 wherein a reversing lever is operably coupled to said planetary gear set to provide its displacement relative to said ring gear to provide said propulsion unit turn.
 8. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical axis for steering the boat, a rotatable steering wheel, a steering cablE connected between said steering wheel and said propulsion unit for rotating it for normal steering, and a control mechanism operatively connected to said propulsion unit for rotating it rapidly through a substantially 180* turn to provide changeover between forward and reverse operation, said mechanism including a reverse control means operably mounted on said steering wheel and manually rotatable a predetermined arcuate distance about the axis of said steering wheel, said last mentioned means coupled to said steering cable for providing said turn.
 9. The combination as set forth in claim 8 wherein said steering wheel is mounted on a shaft, said shaft rotatable independently of said steering wheel to rotate said unit, and wherein said control means comprises a fluid actuator device connected to said shaft for providing its rotation.
 10. The combination as set forth in claim 9 wherein said actuator device comprises a rotary operated fluid motor, said motor having a vane operable between two spaced stops mounted on said steering wheel for providing changeover between the forward and reverse operation of the propulsion unit.
 11. The combination as set forth in claim 9 wherein the rotative movement of said shaft is communicated to said steering cable and to said propulsion unit through a pinion fixed to said shaft and a rack gear in mesh with said pinion and coupled to the forward end of said cable.
 12. The combination as set forth in claim 8 wherein said propulsion unit includes a motor driven propeller mounted on said propulsion unit and swivelable therewith.
 13. In a boat having a propulsion unit mounted on it and rotatable about an upstanding axis for steering the boat, a rotatable steering wheel, a connecting means coupled between said steering wheel and said propulsion unit for rotating it for normal steering, and a control means operatively connected to said propulsion unit for rotating it rapidly through substantially a half circle turn to provide for a reversal of the boat drive, said control means comprising a detent lever mounted on said steering wheel and operably coupled to said connecting means for providing a predetermined rotation of said propulsion unit independently of the rotation of said steering wheel.
 14. In a boat having a propulsion unit mounted on it and rotatable about a substantially vertical axis for steering the boat, a rotatable steering wheel, a steering cable connected between said steering wheel and said propulsion unit for rotating it for normal steering, and a control means operatively connected to said propulsion unit for rotating it rapidly through a turn of substantially 180* to provide a reversal of the boat drive, said control means comprising an electrically operated means mounted on said steering wheel and operable to rotate independently of said steering wheel and displace said cable a predetermined amount to provide said turn to provide the changeover between forward and reverse operation of the boat.
 15. The combination as set forth in claim 14 wherein said electrically operated means comprises the armature of a torque motor, said torque motor further having its field operatively connected to and controlling the direction of movement of said armature and the movement of said steering cable, and a switching means for reversing the polarity across said motor field.
 16. The combination as set forth in claim 14 wherein said steering wheel is coupled to a steering shaft and said electrically operated means is fixed to said shaft and movable between a pair of spaced stops mounted on said steering wheel to provide said turn.
 17. The combination as set forth in claim 14 wherein said wheel is mounted on a steering shaft, said shaft having a pinion gear mounted on it and a toothed rack engageable with the teeth of said pinion gear and attached to one end of said cable for providing the required movement of said steering cable. 